package com.endpoint.gateway.swagger;

import lombok.AllArgsConstructor;
import org.springframework.cloud.gateway.config.GatewayProperties;
import org.springframework.cloud.gateway.route.RouteLocator;
import org.springframework.cloud.gateway.support.NameUtils;
import org.springframework.context.annotation.Primary;
import org.springframework.stereotype.Component;
import springfox.documentation.swagger.web.SwaggerResource;
import springfox.documentation.swagger.web.SwaggerResourcesProvider;

import java.util.ArrayList;
import java.util.List;

//聚合各个服务的swagger接口 设置需要由网关管理的微服务资源名和路径
@Component
@Primary
@AllArgsConstructor
public class SwaggerProvider implements SwaggerResourcesProvider {
    public static final String API_URI = "/v2/api-docs";//swagger2默认的url后缀
    private final RouteLocator routeLocator;//网关路由
    private final GatewayProperties gatewayProperties;


    @Override
    public List<SwaggerResource> get() {
        List<SwaggerResource> resources = new ArrayList<>();
        List<String> routes = new ArrayList<>();
        //取出gateway的route
        routeLocator.getRoutes().subscribe(route -> routes.add(route.getId()));
        //结合配置的route-路径(Path)，和route过滤，只获取有效的route节点
        gatewayProperties.getRoutes().stream().filter(routeDefinition -> routes.contains(routeDefinition.getId()))
                .forEach(routeDefinition ->
                        routeDefinition.getPredicates().stream()
                                .filter(
                                        predicateDefinition ->
                                                ("Path").equalsIgnoreCase(predicateDefinition.getName()) && predicateDefinition.getArgs().get(NameUtils.GENERATED_NAME_PREFIX + "0").startsWith("/api/"))
                                .forEach(
                                        predicateDefinition -> resources.add(swaggerResource(routeDefinition.getId(),
                                                predicateDefinition.getArgs().get(NameUtils.GENERATED_NAME_PREFIX + "0")
                                                        .replace("/**", API_URI)))));
        return resources;
    }

    private SwaggerResource swaggerResource(String name, String location) {
        SwaggerResource swaggerResource = new SwaggerResource();
        swaggerResource.setName(name);
        swaggerResource.setLocation(location);
        swaggerResource.setSwaggerVersion("2.0");
        return swaggerResource;
    }
}